DNA Methylation in Children

In one of the first studies to look at DNA methylation changes in children, NIEHS grantees report that DNA methylation changes detected at birth persist through early childhood. Epigenetic changes such as DNA methylation can occur because of environmental and age-related factors and are thought to be involved in the development of disease.

The researchers used an immunoassay to measure global DNA methylation in 165 children at birth (cord blood) and again at 3 years of age. On average, DNA methylation was significantly higher in the 3-year-old children than at birth (p = 0.01). However, for any individual child, the difference in methylation was less than would be expected by chance. They also found that the mother’s BMI before pregnancy negatively predicted DNA methylation at birth and at 3 years old, even after the researchers accounted for the correlation between DNA methylation at the two time points.Although the health impacts of small changes in DNA methylation aren’t known, the researchers say that their results imply that factors influencing DNA methylation during early childhood may have long-term effects. The findings also point to a need for more research on how factors, such as high BMI before pregnancy, could influence the trajectory of a child’s health.